Mysida

(Mysids)

Phylum Arthropoda

Subphylum Crustacea

Class Malacostraca

Order Mysida

Number of families 4

Thumbnail description
Small shrimplike crustaceans with a flexible carapace enveloping the thoracic region along the sides; stalked eyes; and a well-developed tail fan

Evolution and systematics

Fossil mysids have been dated as far back as the Triassic period, about 248–213 million years ago (mya). A group of fossil crustaceans known as Pygocephalomorpha, which includes a number of Paleozoic genera from the Carboniferous and Permian periods (360–248 mya), is possibly related to the mysids.

Two suborders for the order Mysidacea, the Lophogastrida and Mysida, were recognized in 1883. This arrangement persisted for nearly a century until some researchers proposed alternative taxonomic schemes to explain the relationships among mysidaceans, including raising both suborders to order level. This proposal, which has been sustained by a number of experts, is followed here.

The order Mysida includes four families: Petalophthalmidae, with six genera; Mysidae, with six subfamilies (one, the Mysinae, comprises seven tribes) and almost 140 genera; Lepidomysidae, with only one genus, Spelaeomysis; and Stygiomysidae, also with only one genus, Stygiomysis. The order as a whole includes slightly over 1,000 described species.

Mysids are sometimes known as opossum shrimps because of the marsupium, or external pouch, formed by specially developed plates on the inner sides of the thoracic limbs of adult females.

Physical characteristics

Most mysids are fairly small, between 0.39 and 1.18 in (10 and 30 mm) long. They have a shieldlike carapace that covers the cephalon (head region) and most of the thorax. The carapace is fused with the first three (in rare cases the fourth) thoracic somites (segments). The eyes are usually stalked and movable; the cornea is generally developed with visual elements, but tends to be reduced with increasing depth of habitat. The antennules (antenna 1) and antennae (antenna 2) are biramous (forked). Male mysids typically bear a setose (bristly) lobe, the processus masculinus, on the peduncle of the antennules.

The thorax has eight pairs of pereopods or thoracic limbs, all of which are divided into two branches, an endopod and an exopod. The endopods of the first and sometimes the second pereopod are usually transformed into gnathopods (specialized appendages for feeding), which differ considerably from the remaining limbs. Female mysids have a marsupium made of fewer than seven pairs of lamellae (oostegites or brood plates), in which the embryos are kept until they grow into juveniles. The abdomen consists of six somites, generally similar in form but with the last somite longer than the others. Each of the first five abdominal segments bears a pair of pleopods. The pleopods are biramous, frequently reduced in the female and sometimes in the male. They are often sexually modified in the male. The telson, or posterior extremity of the body, has a pair of appendages known as uropods, which form a well-developed tail fan. A statocyst, which is a tiny organ related to the animal's sense of balance, is usually present in the endopod of the uropods.

Mysids themselves are often glassy or transparent; they can be seen only when the observer notices their black eyes darting about in the water. Most mysids have a body pattern formed by dark star-shaped chromatophores (clusters of pigmented cells) against a light background color. Some species turn dark when placed against a black background; others that are usually light green and found among green algae may change to dark olive. Deep-sea mysids are often red.

Distribution

Mysids are widespread over all continents. They live in a variety of aquatic environments, including coastal and open sea waters, estuaries and other brackish water ecosystems, and continental freshwater lakes and rivers. In addition, a few species have been found in different groundwater habitats and in anchialine (from Greek words that mean "near the sea") caves, which are coastal caves formed from limestone or volcanic rock that are flooded with seawater.

Habitat

Mysids are originally marine crustaceans. They are a highly adaptive group, however, which makes them effective invaders of new habitats, including brackish water and freshwater environments. As a whole, the group is essentially pelagic, although commonly epibenthic, which means that they live on or immediately above the surface of the sediment. Some species burrow into the sediment, live just above the sandy or muddy bottom, or migrate between substrates at the bottom and the surface waters. A few are strictly pelagic species; some live in shallow water in the littoral zone among macroalgae, in crevices along rocky shores, or on sandy beaches. Many species of deep-sea mysids are found on or just above the ocean floor at various depths, including abyssal waters at depths of 18,700–23,622 ft (5,700–7,200 m).

Behavior

Most sand-burrowing and coastal mysids perform a diel (24-hour cyclical) vertical migration, rising and dispersing into the water column at night and returning to deeper water towards dawn. Many are benthic by day and pelagic at night. A few species rest on algae during the day or on stones and cliff ledges; only a few mysids bury themselves in sand. Gastrosaccus throws up sand grains by moving its thoracic limbs while lying on the sand. Paramysis digs ditches in muddy sand with its first three pereopods. This species can dig for long periods of time, producing open ditches as long as 1.9–3.9 in (5–10 cm) within an hour.

Almost all bathypelagic and bottom-dwelling mysids, even those that burrow in sand, rise in the water column at night. The stimulus for this migration may be light intensity; the time it takes the mysids to rise depends on the speed and depth of water currents. This nocturnal pattern is most noticeable during spawning periods, and may be related to the dispersal of young mysids leaving the marsupium. Littoral species sometimes move to deeper water in fall and return to the shoreline in spring or summer.

Some species of mysids form swarms. These swarms may be several miles long and three or more feet in diameter.

Mysids are primarily swimmers; all members of the class can swim up, down, forward, and backward. The females have reduced pleopods and swim with the exopod (external branch) of their pereopods. They hold the exopods out to the sides and rotate them so that the tip describes an oval. They move their limbs continuously in a slightly different phase and draw water from the sides toward their upper surface. In this way two strong currents of water, one parallel to the abdomen and the other some distance from it, drive the body forward. Many species hold their bodies in a horizontal position with the dorsum up while swimming. A few hold the anterior part of their bodies in an almost vertical position.

Some species swim in schools. School formation among mysids depends on optic signals during the day and probably sensitivity to water currents generated by the swimming movements of their neighbors at night.

Mysids that are suddenly disturbed jerk backward by flexing their abdomen and tail fan against their thorax. Bottom dwellers walk slowly on their endopods with their exopods also in constant motion. The eyes and statocysts keep the body horizontal even in the dark. If a mysid is illuminated from the side, it will turn its back toward the light. The angle of turning may be greater than 45° especially if the light is strong. The animal's optic control over body position is able to override the statocysts.

Feeding ecology and diet

Most mysids are filter feeders, removing fine detritus, rotifers, mollusk larvae, diatoms, and other planktonic organisms out of the water while swimming just above the bottom and creating a suspension feeding current. All filter-feeding mysids may also feed raptorially; that is, they may actively capture selected prey from the environment. They have species-specific feeding modes; some species can switch from one feeding mode to another according to food availability.

Members of some mysid genera, including Neomysis and Siriella, have been seen to catch small live crustaceans (copepods, cladocerans, amphipods) as well as small mollusks. Mysids use their gnathopods to seize and feed on zooplankton as well as to strain phytoplankton and particulate debris. These appendages move the food under the animal's mandibles (jaws) and press it against these cutting appendages.

On the other hand, mysids are the prey of many larger predators around the world, including invertebrates, fishes, birds, seals and whales.

Reproductive biology

Male mysids do not actively search for females during reproduction. After shedding a previous brood, the female soon molts and is ready to breed again. At that time she produces a pheromone, or chemical substance that stimulates the antennules or the antennular processus masculinus of nearby males. Mating is very quick and takes place at night. The male lies under the female either head-to-tail and belly-to-belly, or doubles up and grasps the anterior part of the female's abdomen with his antennae. The sperm are either injected into the female's brood pouch or shed between the mating individuals and swept by currents produced by the thoracic appendages into the marsupium. The copulating pair soon separate, and within half an hour the female's eggs are extruded into her brood chamber and fertilized there.

The incubation period and frequency of mating depends on the species and the water temperature, and can range from a few weeks to several months. The young are shed as juveniles with complete sets of appendages. Released mysids need about a month to reach their adult stage at a water temperature of about 68°F (20°C).

Conservation status

The IUCN has placed three species, all anchialine stygobitic mysids (Bermudamysis speluncola, Platyops sterreri, and Stygiomysis hydruntina) on its Red List as Critically Endangered and another one as Vulnerable.

Regression or even complete extinction of mysid populations as a result of human impact has been documented. Mysids are endangered by domestic and industrial pollution of coastal waters; dredging of canals (for land use, fisheries, and navigation); artificial redirection of waters (for river traffic and dykes); groundwater drainage; and the repeated application of pesticides. Subterranean ecosystems are variously threatened by tourism, agriculture, urbanization, and the construction of hydroelectric reservoirs.

Significance to humans

Some mysids are used as fish food in commercial aquaculture. On the Island of Jersey, mysids are compounded into a paste called "cherve," which is sold to mullet anglers for bait. In the Orient, mysids are harvested commercially for human consumption. In Japan, Neomysis intermedia and N. japonica are used for tsukudani, a popular dish made with soy sauce.

Mysids are also used for scientific research. They are excellent experimental organisms because they are easy to collect, relatively easy to handle, and stay healthy in the laboratory for long periods of time.

Species accounts

List of Species

No common name

Spelaeomysis bottazzii

family

Lepidomysidae

taxonomy

Spelaeomysis bottazzii Caroli, 1924, caves near Castro Marina, Otranto, Italy.

other common names

None known.

physical characteristics

This mysid has a short carapace with the last two thoracic somites exposed on the dorsal surface. The rostrum is broadly rounded and the eyes reduced in size. Antennal scale (a lobelike modification of the external branch or exopod of antenna 1) small, without apical suture, outer margin smooth, setose, without terminal spine. The second thoracic limb (pereopod) has developed as a gnathopod; the exopod is well developed. The marsupium in the adult female is composed of seven pairs of oostegites. The sixth and seventh abdominal somites are fused.

distribution

Southern Italy in the Salentine Peninsula around Lecce; the caves of Zinzulusa, Buco dei Diavoli and L'Abisso; artificial wells near Gallipoli and the area around Bari; groundwaters around Gargano.

habitat

This mysid lives in brackish underground waters. It is a euryhaline (tolerant of a wide range of salt concentrations) and eurythermal (adaptable to a broad range of temperatures) species that can live in darkness as well as full or dim light.

behavior

Spelaeomysis bottazzii has been kept alive for more than four months in the laboratory under different lighting conditions, in fresh as well as salt water, with temperatures ranging from 50°F–64°F (10°C–18°C).

feeding ecology and diet

This species feeds on diatoms and other autotrophic (selfnourishing) aquatic microorganisms.

reproductive biology

Spelaeomysis bottazzii has a long period of development in the marsupium as well as a particular reproductive strategy that is not known in other mysids. Females of this species assume an immature form after molting at the end of the incubation period, probably in order to build up nutrition reserves before starting a new reproductive cycle.

conservation status

This species is known from fewer than five localities scattered over an area of less than 38.6 square miles (100 square kilometers) in southern Italy. The IUCN Red List categorizes it as Vulnerable.

significance to humans

None known.

No common name

Amathimysis trigibba

family

Mysidae

taxonomy

Amathimysis trigibba Murano and Chess, 1987, Isthmus Reef, Catalina Island, California, United States.

other common names

None known.

physical characteristics

The size range for adult specimens is 0.1–0.13 in (2.7–3.5 mm). The general form is sturdy. The frontal margin of the carapace leads to a broadly rounded rostral plate. The side margins of the rostrum are evenly convex, partially covering the eyestalks in females. The eyestalks are exposed in males. The posterior margin of carapace leaves the last thoracic somite exposed. There are three tubercles (nodules) on the dorsal surface located between the frontal margin of the carapace and the cervical groove. The eyes are developed, and slightly longer than broad; the cornea is wider than the stalk. The antennal scale has a long apical lobe. Female marsupium has two pairs of oostegites, with the posterior pair considerably larger than the anterior pair. Telson entire, 1.4 times as long as broad; lateral margins naked, proximal two-thirds convex and distal one-third concave; distal margin transverse, one-fifth of maximum width at base, armed with 2 pairs of spines, inner pair two-fifths of telson length.

distribution

Catalina Island, Pacific coast of California, United States.

habitat

Found at a depth of 16.4–75.4 ft (5–23 m). Most abundant within the suspended detritus layer just over the sandy substrate, but also found among low benthic algae growing on rocks.

behavior

Rises at night several feet into the water column where it occurs in densities of about 8.5 per m3.

feeding ecology and diet

Nothing is known.

reproductive biology

Nothing is known.

conservation status

Not listed by the IUCN.

significance to humans

None known.

No common name

Hemimysis margalefi

family

Mysidae

taxonomy

Hemimysis margalefi Alcaraz Riera, and Gili, 1986, dark submarine cave on the northeastern coast of Mallorca in the western Mediterranean, 39°45′N, 3°26′E, at a depth of 39.3 ft (12 m) depth.

other common names

None known.

physical characteristics

Living specimens are bright red in color. The total size of an adult specimen from the anterior margin of the carapace to the distal end of telson ranges from 0.16 to 0.21 in (4.12–5.49 mm). General form robust. Carapace short, emarginate posteriorly, thoracic somites 6 and 7 exposed dorsally; anterior margin forming a broad angle rostrum; cervical groove present. Eyes large, globular, slightly broader than the eyestalk, extended laterally beyond the limits of the carapace; cornea pigment black. Antennal scale lanceolate, narrow, about 5.5 times as long as broad in the broadest part; outer margin straight or slightly curved outward; the proximal 1/5 of its length naked (without a spine or a tooth). Telson short; lateral margins converging distally, armed with 8–11 spines; width at distal end less than half the broadest part; telson cleft for about 1/5 of its length, cleft armed with 20–30 small teeth; apical lobes with a long, strong spine in the distal end.

distribution

Mediterranean; northeastern coast of Mallorca.

habitat

Dark submarine caves.

behavior

This species demonstrated adaptability to a range of temperatures and resistance to acute thermal stress during a series of laboratory experiments.

feeding ecology and diet

Nothing is known.

reproductive biology

Nothing is known.

conservation status

Not listed by the IUCN.

significance to humans

This species is being used to study the physiology of mysids.

No common name

Mysis relicta

family

Mysidae

taxonomy

Mysis relicta Lovén, 1862, cold water lakes in northern Europe.

other common names

None known.

physical characteristics

The total size of mature specimens is 0.59–0.98 in (15–25 mm) long. The antennal scale is only four times as long as it is wide. The exopod on the third pleopod of mature males is well developed and has five segments while the exopod on the fourth pleopod has six. The telson has a wide bifurcated tip.

distribution

Mysis relicta has a circumpolar distribution. It is found throughout the northern latitudes (above 42°N) in the Great Lakes of North America; Green Lake, Trout Lake, and Lake Geneva in Wisconsin; the Finger Lakes of New York; a handful of Canadian shield lakes; Europe, Scandinavia, and Russia. Considered a relict (survivor) of the great glaciers of the Pleistocene Epoch (1.8 million years ago), its natural distribution has been increased by its introduction into continental waters as an addition to the forage base of sport fisheries.

habitat

Cold freshwater. During warm months almost restricted to temperatures range as low as 39.2°F (4°C). It never lives in waters warmer than 57.2°F (14°C). In northern Germany this species does not occur in water with an oxygen concentration lower than 4 cm³/liter; in Wisconsin, however, it lives in water with an oxygen concentration as low as 1 cm³/liter.

behavior

Members of this species are swimmers, remaining in deep cold water during summer and moving in winter to shallower waters to reproduce. They remain near the bottom during daytime and rise at dusk toward the surface to forage. Smaller juveniles often lead the migration, rise higher in the water column than the adults, and are the last to descend. Adapted to living in dark environments, their eyes are easily damaged by strong light.

feeding ecology and diet

Mysis relicta is an opportunistic feeder with both filter-feeding and predatory habits. It feeds mainly on detritus stirred up from the bottom, including diatoms and unicellular algae. The remains of small crustaceans (cladocerans and copepods) have also been found in its stomach contents, however, which indicates that it also feeds heavily on zooplankton and carrion.

reproductive biology

Brood size is positively related to the female's size. A female 0.51–0.59 in (13–15 mm) long carries 10–20 embryos while a female 0.66–0.82 in (17–21 mm) long carries as many as 25–40 embryos. The young are carried in the brood pouch for 1–3 months and leave the marsupium when they are (3–4 mm) long. Mature individuals are 0.51 in (13 mm) long. M. relicta lives for over a year and as long as two years, reproducing once or twice before it dies.

conservation status

Not listed by the IUCN; often introduced as important food item for forage fish.

significance to humans

Mysis relicta is commercially important to fisheries managers as prey for a large number of coldwater fishes, including lake trout, brown trout, rainbow trout, kokanee salmon, various coregonids, burbot, smelts, and alewives.

No common name

Stygiomysis cokei

family

Stygiomysidae

taxonomy

Stygiomysis cokei Kallmeyer and Carpenter, 1996, Temple of Doom Cave (328 ft [100 m] in from cave entrance), 3.7 mi (6 km) northwest of Tulum, Quintana Roo, Mexico, at a depth of 32.8–65.6 ft (10–20 m).

other common names

None known.

physical characteristics

The size of this mysid ranges from 0.35 to 0.86 in (9.0–22.0 mm). The length of the colorless wormlike body is 7.0–7.2 times the width. The length of the carapace is about one-fifth the length of the body. The abdominal somites are smooth and rounded on the dorsal surface. Antenna 1 is about one-half the length of the body. Four paired ventral lamellae or oostegites (typical for Stygiomysis females and a number unique among the Mysida) extending medially and anteriorly from the proximal part of pereiopods 3–6; each oostegite single flexible membranous flap, rounded and elongated anteriorly. The length of the telson is about 1.7–2.0 times its width, or one-sixth the length of the body. It has 15 spines arranged in five groups of three on its posterior margin.

distribution

Coastal inland caves, Quintana Roo, Yucatan Peninsula, Mexico; the type locality, Mayan Blue Cave; Carwash Cave; and Naharon Cave.

habitat

These mysids are stygobites, or cave dwellers. All caves from which this species was collected are completely underwater and entered through water-filled limestone sinkholes. The specimens were collected at depths of 32.8–65.6 ft (10–20 m) in the freshwater layer, occasionally in the upper part of the halocline (a well-defined vertical gradient of salinity). Conditions remained relatively constant with temperatures around 76.1°F–77.9°F (24.5°C–25.5°C), pH 6.8–7.0, low oxygen (near2.0 ppm), and high carbon dioxide levels (44–864 ppm).

behavior

The behavior of S. cokei was observed in a laboratory setting. Open containers of cave water readily lost carbon dioxide, causing the pH to rise. The mysids kept their tails almost straight up at a right angle when the pH was comfortably low. As the pH rose, their tails gradually dropped in proportion to the increase; in extreme conditions, their tails were nearly horizontal. They also lowered their tails to a nearly horizontal position while walking. When the animals were forced off their substrate in the caves or the laboratory, they displayed frantic and ineffective swimming movements. The uropods spread away from the telson to make a wide tail fan when S. cokei is walking. In healthy specimens, the respiratory beating of pereiopods 1–7 occurred in sequences of 3–9 seconds, followed by rest periods that lasted 2–45 seconds. As carbon dioxide levels dropped and the pH rose, their rest periods increased to as long as 50 minutes.

feeding ecology and diet

Primarily filter feeders.

reproductive biology

Nothing is known.

conservation status

Not listed by the IUCN.

significance to humans

None known.

Resources

Books

Bowman, T. E. "Mysidacea." In Stygofauna Mundi: A Faunistic, Distributional, and Ecological Synthesis of the World Fauna Inhabiting Subterranean Waters, edited by L. Botosaneanu. Leiden, The Netherlands: E. J. Brill/Dr. W. Backhuys, 1986.

Brusca, R. C., and G. J. Brusca. Invertebrates. 2nd ed. Sunderland, MA: Sinauer Associates, Inc., 2003.

Calman, W. T. "Crustacea." In A Treatise on Zoology, Part 7, third fascicle, edited by R. Lankester. London: Adam and Charles Black, 1909.

Fretter, V., and A. Graham. A Functional Anatomy of Invertebrates. London: Academic Press, 1976.

Kaestner, A. Invertebrate Zoology. Vol. 3, Crustacea. New York: Wiley-Interscience, 1970.

Mauchline, J. The Biology of Mysids and Euphausiids. Part I, The Biology of Mysids. London: Academic Press, 1980.

McLaughlin, P. A. Comparative Morphology of Recent Crustacea. San Francisco: W. H. Freeman and Company, 1980.

Morgan, M. D. Ecology of Mysidacea (Developments in Hydrobiology, Vol. 10). The Hague, The Netherlands: W. Junk Publishers, 1982.

Müller, H.-G. World Catalogue and Bibliography of the Recent Mysidacea. Wetzlar, Germany: Wissenschaftler Verlag, Laboratory for Tropical Ecosystems, Research and Information Service, 1993.

Murano, M. "Mysidacea." In South American Zooplankton. Vol. 2, edited by D. Boltovskoy. Leiden, The Netherlands: Backhuys Publishers, 1999.

Nesler, T. P., and E. P. Bergerson, eds. Mysids in Fisheries: Hard Lessons from Headlong Introductions. Bethesda, MD: American Fisheries Society, 1991.

Nouvel, H., J.-P. Casanova, and J.-P. Lagardère. "Ordre des Mysidacés (Mysidacea Boas 1883)." In Traité de Zoologie. Anatomie, Systématique, Biologie. Tome VII, Fascicule III A. Crustacés Péracarides (Mémoires de l'Institut Océanographique, 19), edited by J. Forest. Monaco: Musée Océanographique de Monaco, 1999.

Pennak, R. W. Fresh-Water Invertebrates of the United States. 3rd edition. New York: John Wiley and Sons, 1989.

Pesce, G. L., L. Juberthie-Jupeau, and F. Passelaigue. "Mysidacea." In Encyclopaedia Biospeologica, edited by C. Juberthie and V. Decu. Moulis, France and Bucharest, Romania: Société de Biospéologie, 1994.

Ruppert, E. E., and R. D. Barnes. Invertebrate Zoology. 6th ed. Fort Worth, TX: Saunders College Publishing, 1994.

Schmitt, W. L. Crustaceans. Ann Arbor: University of Michigan Press, 1965.

Schram, F. R. Crustacea. New York: Oxford University Press, 1965.

Wittmann, K. J. "Global Diversity in Mysidacea, with Notes on the Effects of Human Impact." In Crustaceans and the Biodiversity Crisis. Proceedings of the Fourth International Crustacean Congress, Amsterdam, The Netherlands. Vol. 1, edited by F. R. Schram and J. C. von Vaupel Klein. Leiden, The Netherlands: Brill, 1999.

Periodicals

Alcaraz, M., T. Riera, and J. M. Gili. "Hemimysis margalefi sp. nov (Mysidacea) From a Submarine Cave of Mallorca Island, Western Mediterranean." Crustaceana 50, no. 2 (1986): 199–203.

Ariani, A. P., and K. J. Wittmann. "Alcuni aspetti della biologia della riproduzione in Spelaeomysis bottazzi Caroli (Mysidacea, Lepidomysidae)." Thalassia Salentina 23, Suppl. (1997): 193–200.

Beeton, A. M., and J. A. Bowers. "Vertical Migration of Mysis relicta Loven." Hydrobiologia 93 (1982): 53–61.

Bowers, J. A., and H. A. Vanderploeg. "In situ Predatory Behavior of Mysis relicta in Lake Michigan." Hydrobiologia 93 (1982): 121–131.

Caroli, E. "Su di un misidaceo cavernicolo (Spelaeomysis bottazzi n. g., n. sp.) di Terra d'Otranto." Atti della Accademia Nazionale dei Lincei Rendiconti, Classe di Scienze Fisiche, Matematiche e Naturali ser. 5, 33 (1924): 512–513.

Cooper, S. D., and C. R. Goldman. "Opossum Shrimp (Mysis relicta) Predation on Zooplankton." Canadian Journal of Fisheries and Aquatic Sciences 37 (1980): 909–919.

De Jong-Moreau, L., and J.-P. Casanova. "The Foreguts of the Primitive Families of the Mysida (Crustacea, Peracarida): A Transitional Link Between Those of the Lophogastrida (Crustacea, Mysidacea) and the Most Evolved Mysida." Acta Zoologica 82 (2001): 137–147.

Evans, M. S., R. W. Bathelt, and C. P. Rice. "PCBs and Other Toxicants in Mysis relicta." Hydrobiologia 93 (1982): 205–215.

Folt, C. L., J. T. Rybock, and C. R. Goldman. "The Effect of Prey Composition and Abundance on the Predation Rate and Selectivity of Mysis relicta." Hydrobiologia 93 (1982): 133–143.

Grossnickle, N. E. "Feeding Habits of Mysis relicta—An Overview." Hydrobiology 93 (1982): 101–107.

Kallmeyer, D. E., and J. H. Carpenter. "Stygiomysis cokei, New Species, A Troglobitic Mysid From Quintana Roo, Mexico (Mysidacea: Stygiomysidae)." Journal of Crustacean Biology 16, no. 2 (1996): 418–427.

Lasenby, D. C., T. G. Northcote, and M. Furst. "Theory, Practice, and Effects of Mysis relicta Introductions to North American and Scandinavian Lakes." Canadian Journal of Fisheries and Aquatic Sciences 43 (1986): 1277–1284.

Lejeusne, C., and P. Chevaldonné. "Cave-Dwelling Invertebrates of the NW Mediterranean: Silent Victims of Global Warming?" Geophysical Research Abstracts 5, 58–96 (2003).

Martin, J. W., and G. E. Davis. "An Updated Classification of the Recent Crustacea." Natural History Museum of Los Angeles County Science Series 39 (2001): 1–124.

Mauchline, J., and M. Murano. "World List of the Mysidacea, Crustacea." Journal of the Tokyo University of Fisheries 64, no. 1 (1977): 39–88.

Moreau, X., D. Benzid, L. De Jong, R.-M. Barthélémy, and J.-P. Casanova. "Evidence for the Presence of Serotonin in Mysidacea (Crustacea, Peracarida) as Revealed by Fluorescence Immunohistochemistry." Cell and Tissue Research 310, no. 3 (2002): 359–371.

Morgan, M. D., and S. T. Threlkeld. "Size Dependent Horizontal Migration of Mysis relicta." Hydrobiologia 93 (1982): 63–68.

Murano, M., and J. R. Chess. "Four New Mysids from Californian Coastal Waters." Journal of Crustacean Biology 7, no. 1 (1987): 182–197.

Pesce, G. L., and B. Cicolani. "Variation of Some Diagnostic Characters in Spelaeomysis bottazzii Caroli (Mysidacea)." Crustaceana 36, no. 1 (1979): 74–80.

Sell, D. W. "Size-Frequency Estimates of Secondary Production by Mysis relicta in Lakes Michigan and Huron." Hydrobiologia 93 (1982): 69–78.

Vanderploeg, H. A., J. A. Bowers, O. Chapelski, and H. K. Soo. "Measuring in situ Predation by Mysis relicta and Observations on Underdispersed Microdistributions of Zooplankton." Hydrobiologia 93 (1982): 109–119.

Other

"Biology of Opposum [sic] Shrimps." Mysidacea Gallery. [6 Aug. 2003]. <http://www.museum.vic.gov.au/crust/mysibiol.html>.

CaveBiology.com. 9 July 2003 [6 Aug. 2003]. <http://www.tamug.edu/cavebiology/sitemap.html>.

European Register of Marine Species. 29 Feb. 2000 [6 Aug. 2003]. <http://erms.biol.soton.ac.uk/lists/brief/Mysidacea.shtml>.

"Misidacei." Dispense di Zoologia. 19 June 2003 [6 Aug. 2003]. <luciopesce.interfree.it/zoologia/mysids.html>.

"Mysidacea: Families, Subfamiles, and Tribes." Crustacea.net. Oct. 2000 [6 Aug. 2003]. <http://www.crustacea.net/crustace/Mysidacea/index.htm>.

"Mysids." Pesce's Home Page. 19 Feb. 2002 [6 August 2003]. <http://www.geocities.com/mediaq/fauna/mysids.html>.

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Estela C. Lopretto, PhD